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29 * @(#)bt_page.c 8.3 (Berkeley) 7/14/94
30 * $DragonFly: src/lib/libc/db/btree/bt_page.c,v 1.4 2005/11/12 23:01:54 swildner Exp $
33 #include <sys/types.h>
42 * Put a page on the freelist.
49 * RET_ERROR, RET_SUCCESS
52 * mpool_put's the page.
55 __bt_free(BTREE *t, PAGE *h)
57 /* Insert the page at the head of the free list. */
58 h->prevpg = P_INVALID;
59 h->nextpg = t->bt_free;
61 F_SET(t, B_METADIRTY);
63 /* Make sure the page gets written back. */
64 return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
69 * Get a new page, preferably from the freelist.
73 * npg: storage for page number.
76 * Pointer to a page, NULL on error.
79 __bt_new(BTREE *t, pgno_t *npg)
83 if (t->bt_free != P_INVALID &&
84 (h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
86 t->bt_free = h->nextpg;
87 F_SET(t, B_METADIRTY);
90 return (mpool_new(t->bt_mp, npg));